The hydrolysis of uranium(VI) in sulfate media

Abstract

The hydrolysis of uranium(VI) has been investigated in 0.10 and 1.0 mol dm -3 Na2SO4 using the potentiometric titration technique. Analysis of the data indicates the presence of the following uranyl hydrolysis species: (UO2)2(OH)2 2+, (UO2)3(OH)4 2+, (UO2)4(OH)7 + and (UO2)5(OH)8 2+ in both media, and additionally, UO2OH+ and (UO2)3(OH)5 + in the lower ionic strength only. The data were used to calculate stability constants for ternary uranyl hydroxo-sulfate complexes. These constants were found to be in excellent agreement with those found in an earlier study at a higher Na2SO4 concentration (1.5 mol dm-3).